Channel structures having protruding portions in three-dimensional memory device and method for forming the same

US11917823B2 · kind B2 · utility

Assignee

• YANGTZE MEMORY TECHNOLOGIES CO., LTD. · CN

Inventors

• Wanbo Geng · 红钢城街道, CN
• Lei Xue · 红钢城街道, CN
• Xiaoxin Liu · 红钢城街道, CN
• Tingting Gao · 红钢城街道, CN

Key dates

• Filing date: Dec 10, 2020
• Grant date: Feb 27, 2024
• Expiry date: Aug 25, 2042

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10B43/35

Abstract

A first opening extending vertically through a dielectric stack is formed above a substrate. The dielectric stack includes vertically interleaved dielectric layers and sacrificial layers. Parts of the sacrificial layers facing the opening are removed to form a plurality of first recesses. A plurality of stop structures are formed along sidewalls of the plurality of first recesses. A plurality of storage structures are formed over the plurality of stop structures in the plurality of first recesses. The plurality of sacrificial layers are removed to expose the plurality of stop structures from a plurality of second recesses opposing the plurality of first recesses. The plurality of stop structures are removed to expose the plurality of storage structures. A plurality of blocking structures are formed over the plurality of storage structures in the plurality of second recesses.